PETR 131 |
| Adsorptive desulfurization of a model fuel over CeO2-based adsorbents was conducted in a flowing adsorption system at 25 oC under ambient pressure without using H2 gas in order to evaluate the desulfurization performance of the adsorbent for producing ultra-low-sulfur fuel. For adsorption test, the capacity and selectivity of CeO2-based adsorbents for various sulfur compounds and the co-existing olefin and aromatic compound were used. Doping Ti and W into CeO2 significantly improved the sulfur removing capacity. The breakthrough sequence of the compounds over the CeO2-based adsorbents was, 1-C8 olefin °Ö toluene < thiophene < benzothiophene < 2-methyl benzothiophene < tetrahydrothiophene. By comparison of selectivity study and computational analysis, it was found that the electron density on sulfur atom might play a more important role than the ¦Ð-electron density in the selective adsorption over the CeO2-based adsorbents. To understand the nature of interactions between adsorbate and adsorbent along with adsorptive desulfurization test, the CeO2-based adsorbents were investigated by an XRD and XPS technique. Considering results of adsorption and XRD, the adsorbents with smaller crystalline size and lattice parameter show the higher performance on adsorption for sulfur removing. In XPS study, the intensity of peak of lattice oxygen with higher binding energy seems nearly proportional to the thiophene removal capacity. |
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Fuel Processing for Hydrogen Production
1:30 PM-5:00 PM, Wednesday, 13 September 2006 Palace -- Presidio Room, Oral
Division of Petroleum Chemistry |